Gilead Sciences (Nasdaq: GILD) and its HIV/AIDS drugs sure have been in the headlines this week. First, the company announced that it was going to allow generic versions of its drugs to be marketed in developing countries. Then, two new studies released Wednesday showed that its HIV drugs can help prevent infections in heterosexuals.

The studies, one run by the University of Washington and the other by the CDC, show that daily intake of antiretroviral medication such as Gilead's pills Truvada or Viread (meds usually taken after infection) reduces HIV infection risk by at least by 62%.  

That's great news. Really great. And so is the company's altruistic move. But what does it mean for Gilead itself? Probably not much.

Mylan (NYSE: MYL), Ranbaxy, and a few other generic-drug makers that signed the agreement with Gilead could benefit, but the profit to Gilead will probably be minimal. According to Reuters, Gilead will receive a 3% to 5% royalty on the sales of the generic version of its products. But in those countries, the prices of the generic version can be just 1% to 2% of the brand-name price. The study results, as the researchers note, "will fundamentally change approaches to HIV prevention in Africa." Emphasis on in Africa.

Could this boost the biotech's HIV-drug sales in developed economies? Well, a similar study using Truvada conducted late last year on gay and bisexual men had similar success, prompting the CDC to issue a fact sheet for doctors. Combined with the two new studies, this could potentially drive additional sales. However, the November study's impact wasn't readily apparent in the first quarter, when U.S. sales of the drug increased only 2% year over year.

Gilead isn't standing still and aims to extend its dominance in the HIV space. Just last month, it signed a licensing agreement with Johnson & Johnson (NYSE: JNJ) about the joint development of HIV drugs. And the company awaits FDA approval of several new combinations, one as early as August. Gilead also has six hepatitis C drugs in the pipeline, with the goal of making its own treatment cocktail. If that's not enough, famed investor George Soros has $58 million invested in the company. So even if this week's news doesn't move the needle much, I still wouldn't bet against Gilead.

Melly Alazraki owns no shares in any of the companies mentioned. The Motley Fool owns shares of Johnson & Johnson. Motley Fool newsletter services have recommended buying shares of Gilead Sciences and Johnson & Johnson and creating a diagonal call position in Johnson & Johnson. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.